drupal/core/modules/block/templates/block.html.twig

{#
/**
 * @file
 * Default theme implementation to display a block.
 *
 * Available variables:
 * - plugin_id: The ID of the block implementation.
 * - label: The configured label of the block if visible.
 * - configuration: A list of the block's configuration values.
 *   - label: The configured label for the block.
 *   - label_display: The display settings for the label.
 *   - module: The module that provided this block plugin.
 *   - cache: The cache settings.
 *   - Block plugin specific settings will also be stored here.
 * - block - The full block entity.
 *   - label_hidden: The hidden block title value if the block was
 *     configured to hide the title ('label' is empty in this case).
 *   - module: The module that generated the block.
 *   - delta: An ID for the block, unique within each module.
 *   - region: The block region embedding the current block.
 * - content: The content of this block.
 * - attributes: HTML attributes for the containing element.
 *   - id: A valid HTML ID and guaranteed unique.
 * - title_attributes: HTML attributes for the title element.
 * - content_attributes: HTML attributes for the content element.
 * - title_prefix: Additional output populated by modules, intended to be
 *   displayed in front of the main title tag that appears in the template.
 * - title_suffix: Additional output populated by modules, intended to be
 *   displayed after the main title tag that appears in the template.
 *
 * @see template_preprocess_block()
 *
 * @ingroup themeable
 */
 @todo Remove the div around content as per http://drupal.org/node/1972122.
#}
{%
  set classes = [
    'block',
    'block-' ~ configuration.provider|clean_class,
  ]
%}
<div{{ attributes.addClass(classes) }}>
  {{ title_prefix }}
  {% if label %}
    <h2{{ title_attributes }}>{{ label }}</h2>
  {% endif %}
  {{ title_suffix }}

  <div{{ content_attributes.addClass('content') }}>
    {% block content %}
      {{ content }}
    {% endblock %}
  </div>
</div>